Message-ID: <29847045df67838cd72dc2dfe830a11642fb7153.camel@j-davis.com>
Subject: Re: Default setting for enable_hashagg_disk
From: Jeff Davis <pgsql@j-davis.com>
To: Tom Lane <tgl@sss.pgh.pa.us>, Peter Geoghegan <pg@bowt.ie>
Cc: Stephen Frost <sfrost@snowman.net>, Alvaro Herrera
 <alvherre@2ndquadrant.com>, Andres Freund <andres@anarazel.de>, Bruce
 Momjian <bruce@momjian.us>, Robert Haas <robertmhaas@gmail.com>, David
 Rowley <dgrowleyml@gmail.com>, Justin Pryzby <pryzby@telsasoft.com>,
 Melanie Plageman <melanieplageman@gmail.com>, Tomas Vondra
 <tomas.vondra@2ndquadrant.com>,  "pgsql-hackers@postgresql.org"
 <pgsql-hackers@postgresql.org>
Date: Fri, 10 Jul 2020 11:34:44 -0700
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On Fri, 2020-07-10 at 13:46 -0400, Tom Lane wrote:
> I looked over Peter's patch in [1], and it seems generally pretty
> sane to me, though I concur with the idea that it'd be better to
> define the GUC as a multiplier for work_mem.  (For one thing, we
> could
> then easily limit it to be at least 1.0, ensuring sanity; also, if
> work_mem does eventually become more dynamic than it is now, we might
> still be able to salvage this knob as something useful.  Or if not,
> we just rip it out.)  So my vote is for moving in that direction.

In that case, I will hold off on my "escape-hatch" GUC.

Regards,
	Jeff Davis